The invention discloses a silica gel material modified by basic amino acid and a preparation method and application of the silica gel material. The preparation method comprises the step of grafting basic amino acid to silica gel by a chemical method, specifically, silicon hydroxyl on the silica gel reacts with a silica gel coupling agent, formed active sites are connected with basic amino acid with carbamazepine (CBZ) protection, a palladium carbon agent is used for removing the CBZ protection, and the silica gel material modified by the basic amino acid is prepared and obtained. According tothe silica gel material modified by basic amino acid and the preparation method and application of the silica gel material, basic amino acid is novelty connected to a silica gel basic material, the properties that the grain size of the silica gel is small, the heat stability is high and the like are maintained, the basic amino acid has a plurality of functional amino sites and can combine with heavy metal ions in a high affinity mode, and the absorption capacity of heavy metal is improved. In addition, the silica gel material modified by basic amino acid can efficiently remove the heavy metalin water and a tea polyphenol aqueous solution, and the loss of tea polyphenol is small. The silica gel material can be well applied to processing of industrial waste water and removal of the heavy metal in tea polyphenol and a tea beverage, and the application prospect is wide.